Work

Moderate grazing enhances the connectivity and stability of social-ecological systems: Insights for zoned governance in the Yarlung Zangbo River Basin

Year: 2026

Type: article

Abstract: Grazing sustains livelihoods but poses severe challenges to ecological security. Unraveling the impact of grazing intensity on integrated social-ecological systems (SESs) is imperative for reconciling this conflict. However, existing research primarily focuses on the ecological effects of grazing, lacking an integrated analysis from a coupled social-ecological perspective. Focusing on the Yarlung Zangbo River Basin (YZRB), this study applied network analysis to construct SESs and characterize their evolutionary trajectories under grazing pressure. Threshold regression models were employed to uncover the nonlinear responses and critical thresholds of the SESs to grazing intensity, ultimately leading to a threshold-based zoning governance scheme. Results showed that from 2000 to 2020, the SESs evolved toward greater connectivity and stability. However, increasing grazing intensity disrupted the structure of the SESs: density, links, average degree, and transitivity declined by 15.30 % on average, accompanied by an 18.06 % increase in vulnerability. Meanwhile, hub nodes shifted from vegetation to landscape structure factors, and modules gradually decoupled. Further analysis revealed that the responses of the SESs to grazing intensity were nonlinear: both low and high grazing intensities compromised the structure of the SESs, whereas moderate grazing enhanced their connectivity and stability. Based on response thresholds, the YZRB was divided into four subzones: ecological sensitivity zone (< 2.8 sheep unit per hectare (SU/ha)), adaptive transition zone (2.8–4.6 SU/ha), coordinated development zone (4.6–6.0 SU/ha), and risk prevention zone (> 6.0 SU/ha). This study provides adaptive management strategies for the YZRB and offers a methodological reference for the governance of coupled systems facing similar challenges worldwide.

Source: Geography and sustainability

DOI: 10.1016/j.geosus.2026.100496